Technical drawings are an important element within any engineering business. However, when relying on 2D drawings as the primary communication method, it is often easy to misinterpret the initial intention. A 3D model removes the possibility of misunderstanding and by utilizing model based definition a fully defined part can be created and used in subsequent downstream processes.
Technical drawings today
Before we look at the future of technical drawings, we should look at their present function in an enterprise.
Technical drawings are an important way of communication between all parties involved in order processing. The workpiece or assembly is completely described for production without any further inquiries. Therefore, drawings are an important part of the contract in the procurement process.
Creating a drawing is very time-consuming, even with an existing 3D model. It takes time to position all the required views on the sheet and add all the necessary dimensions and annotations. Often queries come from the production department, even though the components are supposed to be completely described within the drawing.
This is not surprising when you consider that the designer translates his 3D CAD model into a 2D drawing and the manufacturer then converts this 2D drawing back into a 3D component. With all these manual steps, a loss of information is inevitable and error reduction would only be possible through automation. Because the information in a technical drawing is comprehensible for humans, the process can be automated to a limited extent. We need new solutions if we want to simplify the transfer of data from design to production.
Model based definition
So, wouldn't it be great if the designer, who knows all the requirements of the component like no one else, could enter all the information directly into the 3D model and the manufacturer could read it directly?
Using Model Based Definition (MBD), the designer can create a fully defined 3D model within Inventor. Important information, such as material or article number, can be linked to the model using meta data (iProperties). The function of the component can be ensured by tolerance dimensions combined with geometric dimensioning and tolerancing (GD&T), as well as surface quality specifications. Information for holes and threads are read directly from the model and special requirements can be annotated. Additional general information like profile notes, surface quality or tolerances can also be provided.
Tolerances defined within MBD can be optimized directly in the model via the Inventor Tolerance Analysis, regarding its function and manufacturing costs. Due to this link all information is saved within the model and always available.
The fully defined 3D model can be used directly for programming tool paths for CNC-machines or coordinate measurement machines. This saves a lot of time and combined with a proper data management system, the latest released version will always be available.
Technical drawings in the future
Using MBD significantly simplifies or even eliminates the necessity to create a drawing.
Companies who sub contract their manufacturing have greater success using this workflow. Instead of producing a full drawing to get a quote for work, MBD can be attached to the model and shared. The advantage is a quicker turnaround for quotations, with better feedback from the manufacturer earlier in the design process. The contract documents can be prepared later in the procurement process, when a vendor has been selected.
Companies who manufacture in-house can implement a consistent version-dependent and associative process from design to production and quality management report about significant time savings in everyday work. The design department has no redundant management and control of drawings. Production always have access to the latest released version, in combination with an associative CAM system, programming is much faster.
Single source of truth
Because technical drawings are essential in the procurement process most companies will not be able to eliminate 2D drawings in the near future. Nevertheless, MBD helps you to improve productivity and efficiency, because all information is stored directly within the model in human- and machine-readable format as a single source of truth.
Learn more about Model Based Definition (MBD) in Inventor
